【作者】 葛维亚；

【导师】 陈林； 葛红；

【作者基本信息】 西南大学 ， 花卉学， 2009， 硕士

【摘要】 菊花别名鞠、寿客、帝女花、黄华等,是我国的传统名花,栽培历史已有1600多年,与兰花、梅花、竹并列合称为“四君子”。菊花色彩艳丽,姿态万千,不畏严寒,傲雪怒放,自古以来深受人们的喜爱,而且菊花的用途非常广泛,地被菊及岩菊可布置花坛、花境及岩石园:杭菊可入药,或作清凉饮料用。另外,菊花是世界上四大切花之一,近年来菊花的销售量在切花总量中一直位居榜首,约占总量的30%。菊花作为无性繁殖的观赏植物,一些品种花粉极少或没有花粉,且遗传上高度杂合且为多倍体,比较适合辐射诱变育种。本试验研究了不同剂量⁶⁰Co-γ射线辐照菊花‘神马’（‘Jinba’）的组培苗和地被菊Zh99-1的种子,从形态指标、叶片相对含水量、叶绿素含量、种子发芽率和抗氧化酶系统等方面研究辐射对菊花M1代的生物效应。以期为菊花辐射有诱变育种提供理论支持。主要结果如下:1.⁶⁰Co-γ射线辐照‘神马’组培苗的半致死剂量在20Gy左右,继代培养可提高辐射后代的成活率,增加变异群体的数目。射线辐射对M1代大多数性状产生了抑制作用。射线辐射对‘神马’M1代的叶片相对含水量无显著影响,M1代叶片相对含水量显著低于对照,说明辐射处理降低了M1代菊花的叶片保水能力。辐射对‘神马’M1代的叶绿素含量无显著影响,高温处理使辐射M1代的叶绿素含量显著上升。地被菊种子在受到辐射处理后,发芽势随辐射剂量的增加而逐渐降低,低剂量（10Gy和20Gy）对种子发芽率无明显影响,高剂量（30Gy、40Gy和50Gy）显著抑制了种子的发芽率,剂量越高抑制作用越明显。2.⁶⁰Co-γ射线辐照后‘神马’组培苗M1代叶片H₂O₂含量显著低于对照,可能与过氧化氢酶（CAT）活性和谷胱甘肽还原酶（GR）活性的显著升高有关。没有经过辐射处理的菊花叶片,在受到高温处理后也出现了H₂O₂含量的显著下降,可能与CAT活性和过氧化物酶（POD）活性的显著升高有关。高温处理后辐射M1代H₂O₂含量的显著下降同时伴随着GR活性的显著升高。低剂量（10Gy和20Gy）辐射处理使‘神马’组培苗M1代超氧化物歧化酶（SOD）活性显著提高,较高剂量（30Gy）则无明显影响。表明菊花在受到不同胁迫时,发挥主要作用的抗氧化酶可能不同。3.⁶⁰Co-γ射线辐照后M1代地被菊幼苗,随剂量增加H₂O₂含量先增加后减少,10Gy辐射处理除GR活性显著降低外,对其他抗氧化酶活性均无显著影响。从20Gy辐射处理开始随辐射剂量增加CAT活性也出现了先增加后减少的趋势,而SOD随辐射剂量增加活性逐渐提高。20Gy及其以上各剂量处理使地被菊辐射处理后代成活率急剧下降,POD活性却急剧升高,说明POD活性可以作为地被菊种子辐射后代成活率的代谢指标。4.⁶⁰Co-γ射线辐照处理对‘神马’组培苗M1代丙二醛（MDA）含量无显著影响,高温处理使辐射M1代MDA含量显著高于对照,辐射处理可能降低了M1代菊花的耐热性。10Gy辐射处理对M1代地被菊幼苗MDA含量无显著影响,20Gy辐射处理显著提高了MDA含量并且随着剂量的升高MDA含量逐渐增加。更多还原

【Abstract】 Chrysanthemum is Chinese traditional flower and it’s cultivation history has been 1,600 years,with the orchid,plum blossom,bamboo tied together referred to as the“four gentlemen.”Colorful chrysanthemums was very popular all the time,and it has extensive use,ground-cover chrysanthemum and rock chrysanthemum can be arranged flower beds,flower and rock garden habitats;Florists Daisy can be medicine or soft drinks.In addition,the chrysanthemum is one of the world’s four major cut flowers in recent years,cut chrysanthemum has been the largest sales share in the cut-flower trade, accounting for about 30%of the total.As vegetative propagation of ornamental plants, lots of chrysanthemum varieties have a little or no pollen,and a high degree of genetic heterozygosity and polyploid makes chrysanthemum suite for radiation-induced breeding.In this experiment we researched different doses of ⁶⁰Co_-γ,ray irradiated tissue culture seedlings of cut Chrysanthemum’Jinba’and seeds of Zh99-1,research the biological effects of Chrysanthemum M1 generation with the form of indicators,leaf relative water content,chlorophyll content,seed germination rate and antioxidant enzyme systems.It can provide theoretical support for mutation breeding of chrysanthemum.The main results are listed as follows:1.The semi-lethal dose ofγray irradiation tissue culture seedling of ’Jinba’ is about 20Gy.Subculture can increase the survival rate of offspring after radiation,increasing the number of variant groups.Radiation inhibits the majority of traits of M1 generation. Ray radiation have no significant effect on the leaf relative water content of ’Jinba’ M1 generation,but after high temperature treatment the relative leaf water content of M1 with radiation was significantly lower than control.The results showed radiation reduced the capacity of leaves water-retention on M1 generation of chrysanthemum. Radiation have no significant effect on chlorophyll content of ’Jinba’ M1 generation, high temperature treatment made a significant increase in chlorophyll content on M1 generation.Chrysanthemum seeds were treated by radiation,with the germination potential decreased in radiation dose increased.Low-dose（10 Gy and 20 Gy）on the seed germination rate have no significant impact,high-dose（30 Gy,40 Gy and 50 Gy） significantly inhibited the seed germination rate,the higher the dose the more obvious inhibition.2.The H₂O₂ content of leaves was significantly lower than control after ’Jinba’ tissue seedlings of M1 generation were irradiated byγ-ray,the results may be related to the activity of catalase（CAT）and glutathione reductase（GR）significantly increased. The chrysanthemum leaves have not been dealt by radiation with high-temperature treatment also appeared the H₂O₂ content in a significant drop.The results may be related to the activity of CAT and peroxidase（POD） increased significantly.After high temperature treatment of radiation-generation of M1,the H₂O₂ content decreased significantly at the same time along with the GR activity increased significantly. Low-dose（10Gy and 20Gy） radiation made tissue of ’Jinba’ M1 generation’s superoxide dismutase（SOD） activity was significantly increased;a higher dose（30Gy） had no significant effect.This results show that chrysanthemum by the different stress,play a major role in the antioxidant enzymes may be different.3.The M1 generation plants that irradiated byγray,with the dose increased,the H₂O₂ content first increased and then reduced.10Gy radiations in addition to a significant reduction in GR activity,the activity of other antioxidant enzymes were not significantly affected.From the beginning of irradiation with 20Gy radiation dose increased CAT activity also increased after the first downward trend,while the SOD activity increased with the radiation dose a gradual increase.Dose of 20Gy and above all sharp decline the survival rate of radiation future generations,but there was a dramatic increase in POD activity that can be used as a metabolic marker of radiation future generations’survival rate on ground-cover chrysanthemum.4.γray irradiation treatment on the tissue of ’Jinba’ M1 generation have no significant impact to content of malondialdehyde（MDA）.High temperature treatment made MDA content of radiation M1 significant higher than the control,radiation may reduce the heat resistance of chrysanthemum’s M 1 generation.10Gy radiation treatment on the M 1 by the chrysanthemum seedlings have no significant effect to MDA content, 20Gy radiation treatment significantly increased MDA content and increased with the dose gradually increased MDA content.更多还原